It is known to use a silicide layer at a contact opening to improve the contact between a conducting material (e.g., copper, tungsten) filling the contact opening and the underlying substrate. Typically the contact opening opens to a source, drain, and gate region (i.e., a heavily doped silicon region) formed in the underlying substrate (CMOS). However, a contact opening may open to other regions or layers as well. There are many different processes and known ways to form a silicide layer and a contact opening. Also, there are wide varieties of materials that are typically used for the silicide layer. During the process of forming the contact opening, etching steps may lead to oxidation of the silicide layer. Such oxidation is usually undesirable because the oxidized portions often have a higher contact resistance. Also during such oxidation, silicon of the silicide layer may be consumed forming silicon dioxide, for example. Hence, there is a need for a way to reduce the amount of oxidation experienced by the silicide layer during the etching step(s) used to form the contact opening and/or used to remove an etch stop layer.